Preheat oven to 375 degrees F (190 degrees C). Grease a 10x10-inch baking dish.
In large bowl, combine flour, salt, baking powder and 1 cup sugar; stir. Add butter, milk and vanilla; beat with electric mixer for 2 minutes, or until smooth. Pour mixture into pan and cover evenly with cherries.
Heat cherry juice in microwave or in small saucepan, until just simmering. Sprinkle 1/2 cup of sugar over cherries, and pour hot cherry juice on top. Bake 40 to 45 minutes, or until pick inserted in center comes out clean.